[20.04 FEAT] libvirt: Add support for PCI multifunction adapter hot plug/unplug in libvirt

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== Comment: #0 - Frank P. Novak <email address hidden> - 2016-06-29 18:37:58 ==
Libvirt currently supports cold passthrough of PCI multifunction adapters. However, it doesn't support proper hot plug/unplug of all the functions of these adapters.

This bug tracks the development work needed to enable PCI hot plug/unplug of multifunction adapters in libvirt.

== Comment: #13 - Leonardo Augusto Guimaraes Garcia <email address hidden> - 2017-01-18 18:30:50 ==
Shiva has been working on this one upstream. However, other changes going upstream related to the multi-PHB support in ppc64 are probably going to affect the work being done by Shiva. Given that this is not being ready upstream soon, moving this one to Ubuntu 17.10.

[Christian Ehrhardt  (paelzer)]

Hi,
thanks for opening this bug to track that work.
I read this is known to be incomplete yet, please let us know when there is any code/release that be considered for inclusion.

[Christian Ehrhardt  (paelzer)]

Ping - Polling for related commit ID's for p9 support

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------- Comment From <email address hidden> 2017-06-14 10:16 EDT-------
Hi Christian,

This is not POWER9 specific. Actually, not even Power specific. This is still being worked upstream.

[Christian Ehrhardt  (paelzer)]

Thanks to clarify - I expected just as much but wanted to be sure.
So we keep it open and incomplete for now and might punt it to 18.04 later on if it takes more time.

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------- Comment From <email address hidden> 2017-07-20 05:08 EDT-------
*** Bug 156863 has been marked as a duplicate of this bug. ***

[Frank Heimes (fheimes)]

The mentioned "Bug 156863" is obviously a bugzilla bug.
Is it also a duplicate of another bug in Launchpad?

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------- Comment From <email address hidden> 2017-08-07 15:22 EDT-------
(In reply to comment #22)
> The mentioned "Bug 156863" is obviously a bugzilla bug.
> Is it also a duplicate of another bug in Launchpad?

No. It has been marked as a duplicate by error.

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------- Comment From <email address hidden> 2017-09-14 10:55 EDT-------
Madhu,

Could you please point the upstream commit IDs for this feature? Or, given that Ubuntu 17.10 is using libvirt 3.6 now, hopefully this already has the needed commits.

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------- Comment From <email address hidden> 2017-10-03 09:51 EDT-------
Hi Leonardo, This is not yet upstream, and will be too late for 17.10, so re-targeting to 18.04.

Thanks,
Shiva

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------- Comment From <email address hidden> 2018-02-12 00:27 EDT-------
@shiv will this be targeted for Ubuntu 18.04?

[Manoj Iyer (manjo)]

Looks like we are still waiting on the code to be upstreamed. Any updates on the upstream status ?

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------- Comment From <email address hidden> 2018-02-14 13:40 EDT-------
This is not upstream yet. Shiva is working on it.

[Manoj Iyer (manjo)]

IBM, 18.10 feature freeze is on the 23rd of Aug, any news on the upstream status of this patch?

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------- Comment From <email address hidden> 2018-08-21 01:20 EDT-------
Patches posted upstream and pending review.

[Manoj Iyer (manjo)]

Have the patches made its way upstream? if so could you please post those links here?

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------- Comment From <email address hidden> 2018-12-06 02:13 EDT-------
The latest patch set is here:
https://www.redhat.com/archives/libvir-list/2018-March/author.html#00729

For now will also reduce the priority and will look into the priority of this more.

[Andrew Cloke (andrew-cloke)]

From looking at the maillist in comment #16, it would appear that this patchset is still in discussion.

[Andrew Cloke (andrew-cloke)]

Marking as incomplete while waiting for the patchsets to land upstream.

[Andrew Cloke (andrew-cloke)]

Updated title to reflect new 19.10 target.

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------- Comment From <email address hidden> 2019-07-01 10:27 EDT-------
Current progress: I chose to split the patch series into smaller chunks to make it easier to review and to be pushed. First part, 10 patches (out of 30) was sent to the Libvirt mailing list last Wednesday, June 26th [1]. It is still pending review. Before sending this first part I've sent a RFC to the mailing list reviving the discussion [2], and the community seems to approve it (or, at least, not rejecting it fiercely).

Still, I am not sure about the 19.10 target. Feature freeze for 19.10 is August 22nd (correct me if I'm wrong), so we have 30 patches to be pushed in 8 weeks. It is doable, but depends on how fast I can work it with the community on the reviews.

[1] https://www.redhat.com/archives/libvir-list/2019-June/msg01268.html
[2] https://www.redhat.com/archives/libvir-list/2019-June/msg00703.html

[Christian Ehrhardt  (paelzer)]

It's your targets/milestones - if 20.04 makes more sense for your upstreaming (and it seems it does) that seems fine for us.

[Andrew Cloke (andrew-cloke)]

Moving to target 20.04.

[Christian Ehrhardt  (paelzer)]

FYI: see [1] and related posts for further upstream activity.

[1]: https://www.redhat.com/archives/libvir-list/2019-August/msg00640.html

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------- Comment From <email address hidden> 2019-09-13 08:12 EDT-------
The first set of patches of the feature was pushed to Libvirt this last Monday, Sept 9th. The set contained enhancements/fixes in the test framework for the more sophisticated PCI multifunction tests that will come.

It is also worth mentioning is that I proposed a change in the PCI multifunction hot-unplug mechanism of the pseries machine in QEMU. The change was accepted and it is upstream. You can read more about it here [1], but the result is that the design of the multifunction hot-unplug in Libvirt can be simplified after this change.

I'll be re-testing the whole patch series after the recent changes in Libvirt master branch, then I'll make further adjustments considering that QEMU change I mentioned above. I'll end up submitting what's left of the feature in a single series, instead of breaking down in smaller pieces, given that the remaining patches are now quite tied up together.

[1] https://github.com/qemu/qemu/commit/02a1536eee333123c7735cd36484da53b860fbb7